I was an active member but I had problems in my real life because people recognize me there. I would like to change my nick but is impossible so I was thinking "Why not invite myself with another email and create a new me?" ...how can I do it? Since I have had problems I've stop writing here

You may not re-invite yourself to get another account. The new account will be merged into the old one (nothing to gain here) and your invitiation privileges will be removed permanently. It is because it's against the Community Rules to have more than one account for this or any other purpose.

User Names are not usually changed either. However, if you want to try, use the "Contact Us" link at the bottom of the page and plead your case to administration ... explain exactly what is going on ... it will be confidential, so tell the whole story. They will decide if there is due cause to change your user name or not.